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Biomedical subjects

P Degoulet

Publications and source records attributed to P Degoulet.

At least 73 records · Page 4Linked to original sources

A software engineering approach for medical workstations development.

Multimedia medical workstations represent the natural tool for accessing the hospital information system environment. They are complex medical systems that have to gather, in a single framework, a large collection of components dealing with multimedia medical objects. To remain current with both medical practice and with advances in the computer science field, they have to allow the iterative addition of new functions to the set of existing ones. In this paper, after a survey of commonly required medical workstation functional components, we shall try to discuss how a software engineering approach can streamline the development of a medical workstation. Different software engineering tools needed to build the functional components of a workstation are described. Their integration in a single dedicated environment is considered through four perspectives: data, presentation, communication and control. Benefits and limitations of an object-oriented approach are discussed.

Computer Communication Networks↗

The HELIOS medical software engineering environment.

The aim of the HELIOS project is to create an integrated Software Engineering Environment (SEE) to facilitate the development and maintenance of medical applications. HELIOS is made of a set of software components, communicating through a software bus called the HELIOS Unification Bus. The object oriented paradigm is used both as the basic structure for building the software components and as the methodology for modelling, storing and retrieving the entities and procedures used in an application. Development standards include UNIX as operating system and X Window/MOTIF as windowing environment. One of the target applications for the HELIOS prototype is the development of a multimedia medical workstation as a front end to a hospital information system.

Computer Systems↗

The component-based architecture of the HELIOS medical software engineering environment.

The constitution of highly integrated health information networks and the growth of multimedia technologies raise new challenges for the development of medical applications. We describe in this paper the general architecture of the HELIOS medical software engineering environment devoted to the development and maintenance of multimedia distributed medical applications. HELIOS is made of a set of software components, federated by a communication channel called the HELIOS Unification Bus. The HELIOS kernel includes three main components, the Analysis-Design and Environment, the Object Information System and the Interface Manager. HELIOS services consist in a collection of toolkits providing the necessary facilities to medical application developers. They include Image Related services, a Natural Language Processor, a Decision Support System and Connection services. The project gives special attention to both object-oriented approaches and software re-usability that are considered crucial steps towards the development of more reliable, coherent and integrated applications.

Computer Communication Networks↗

The HELIOS Medical Connection Services.

This paper presents the design and implementation of the HELIOS software component that deals with integration of medical applications in health information networks. The problem of interoperability between health information systems based on different data exchange syntaxes is first discussed. A meta-model, relying on CEN TC251 recommendations, is then presented as a possible solution to this problem and a message description language including these recommendations is proposed. Using this meta-model, the Medical Connection Services that comprises a generic message processing automaton, a resource manager and a mapper is able either to interpret messages expressed in a given syntax (e.g., EDIFACT, ASTM) and map them to the application objects or to automate the translation of the messages in another syntax. Special focus is given on the position of the Medical Connection Services within the HELIOS integration strategy (i.e., through data, presentation and communication). The problem of semantic heterogeneity is then discussed.

Computer Communication Networks↗

ARTEMIS-2: an application development experiment with the HELIOS environment.

A medical application is a highly complex system that embraces many data types and a very large number of data processing functions and methods. The development of integrated software engineering environments has deeply changed the conception of applications and the profile of the application developers. In this paper, we address the problem of the development process of a specific multimedia application, called ARTEMIS, within the distributed HELIOS environment. The application is intended to manage information about hypertensive patients, in particular, retrieval and display of administrative, clinical and biological data and display and analysis of digital angiography images and medical reports. The objective is to show how the developer can use, customize and organize the services HELIOS provides. A particular focus is set on reuse strategies and integration during the development process. A scenario has been realized and illustrates the current state of the application. The discussion focuses on the advantages of such distributed environments in medical application development.

Computer Communication Networks↗

The HELIOS Unification Bus: a toolbox to develop client/server applications.

In the medical domain, new developments commonly rely on client/server architectures. But face to distributed environments, the software developers encounter a tremendously increasing complexity when building integrated applications. This paper presents the HELIOS Unification Bus (HUB), a communication integration framework for the HELIOS medical software engineering environment that allows the exchange of data between components that can be hosted on heterogeneous machines linked by a network. The HUB is developed as a C++ toolbox over UNIX and TCP/IP. It includes a message routing entity called router and a generic application programming interface (API), implemented as a C++ library, that allows to build easily software components compliant with the standardised HELIOS language. Messages conveyed by the bus are composite objects that are serialized to be transmitted over the bus using the ASN.1 ISO presentation protocol. The article describes the use of the bus to ease the development and execution of distributed medical applications and its role from the communication integration standpoint.

Computer Communication Networks↗

A reuse oriented Development Database: the HELIOS Object Information System.

This paper describes the Development Database of a Software Engineering Environment (SEE), that couples reuse and object-oriented technologies. We propose a classification model for the repository of reusable components that is a support for an efficient retrieval mechanism, and a reusable component model that considers components of large and low-granularity levels (e.g., application frameworks and methods of a given class). The reusable component model is based on the underlying idea that development components are not operational components since they do not have the same purpose. This model first represents each component as an aggregation of other sub-components, together with all information needed for its retrieval (e.g., classification and facets), its under-standing (e.g., informal functional description) and its dependencies with other development components, in particular the applications in which it occurs, since applications are considered also as abstract development components. This approach was tested thanks to an existing application which was loaded into the SEE. From that moment, it was possible to regenerate a new application in a reasonably short time. Moreover, the existence of a retrieval tool permits to validate the development components classification, but also put forward the importance of the qualification step. In particular, the versioning should be carefully processed. Furthermore the fact that all the development objects are built on an homogeneous model allows easier tools management and interapplication reusability.

Database Management Systems↗

Using a meta-model to build a connection service in an object oriented medical application development environment.

Interoperability is a key issue in distributed health information systems. This paper presents the design and implementation of the Connection Service (CS) component of the HELIOS medical software engineering environment. An exchange message meta-model based on CEN TC251 recommendations and a message description language are proposed. Using this meta-model, the CS is able either to interpret messages expressed in a given syntax (e.g., EDIFACT, ASTM) and map them to the application objects or to automate the translation of the messages in another syntax. It is concluded that this meta-model approach contributes to the management of semantic heterogeneity.

Computer Communication Networks↗

[Evaluation of computer-assisted instruction methods. Apropos of 26 comparative studies published between 1989 and 1992].

Information and knowledge processing technologies have contributed to the development of Computer assisted instruction (CAI) applications. Multimedia technologies will increase the possibilities of these programmes in the future. However the evaluation of the software as well as the other technologies is necessary. The authors have tried to quantify the contributions of CAI analysing the literature referenced in MEDLINE from 1989 to 1992. On the 470 papers indexed with the key-word "Computer Assisted Instruction", 56 studies take evaluation into account. Only 26, that is 5.5%, presented a clear and explicit methodology of evaluation. On the 26 studies, 16 were considered with positive result and among these, 6 presented a statistical significance. The conditions and the criteria of the evaluation studies do not permit a meta analysis. Is is necessary to develop standardized evaluation criteria to estimate the quantitative and qualitative impact of the CAI technics on the educational process and their own pedagogical contribution.

Computer-Assisted Instruction↗

Description and representation of segmented renal arteries from angiograms.

This paper presents the first prototype of a system that uses syntactic techniques to describe normal and abnormal aspects of segmented renal arteries from angiographic images. The system is one part of a full understanding system devoted to the interpretation of angiograms. Its purpose is to provide symbolic descriptions of lesions that can further contribute to an accurate diagnosis from the image. The prototype consists of a modular system that takes artery outlines as input and provides a structural description of the artery as output in the framework of a precise quantification scheme. Each module yields heuristic parameters that influence the resulting description. The system is intended to be a tool to study independently the role of these different parameters in the inter and intra observer variability.

Humans↗

[Cardio-respiratory complications of sleep apnea in obese patients].

The cardio-respiratory complications of sleep apnea syndrome have been prospectively assessed in 60 patients with massive obesity and free of chronic obstructive lung disease while the associated cardiovascular diseases and the alterations of pulmonary function were taken into account. These cardio-respiratory complications were observed only in patients with a number of apneas per hour of sleep greater than 20. The sleep apneas induced nocturnal hypoxemia that is frequently severe and independently correlated to the apnea index, diurnal hypoxemia and hypercapnia that are usually moderate, and presumably left ventricular hypertrophy that is not related to the development of daytime hypertension. However the nocturnal apneas were not associated with the development of an impairment of right or left ventricular function, or with the occurrence of cardiac arrhythmias or conduction disturbances. The absence of severe cardiac complications in this study may be related to the fact that the patients were relatively young and that the sleep apnea syndrome was diagnosed at an early stage of evolution. The findings of this study could help to define a more rationale approach in several therapeutic indications of sleep apnea syndrome.

Adult↗

Distribution and communication in software engineering environments. Application to the HELIOS Software Bus.

Modularity, distribution and integration are current trends in Software Engineering. To reach these goals HELIOS, a distributive Software Engineering Environment dedicated to the medical field, has been conceived and a prototype implemented. This environment is made by the collaboration of several, well encapsulated Software Components. This paper presents the architecture retained to allow communication between the different components and focus on the implementation details of the Software Bus, the communication and integration vector of the currently running prototype.

Computer Communication Networks↗

Computer-assisted techniques for evaluation and treatment of hypertensive patients.

An integrated approach, progressively implemented in the ARTEMIS system since 1975, is described for the computerized management of hypertensive patients. From a medical point of view, computerized programs can be used to memorize patients' individual records and profiles, to facilitate patient management and follow-up, to store medical knowledge about hypertension and to provide facilities for decision making at the level either of the individual patient or of the population followed up. From a technical point of view, the methodology used integrates data and knowledge management facilities into the same software. Five hypertension clinics are presently using the system in France and more than 22,000 records have been registered. Answer rates to 12 mandatory questions regarding past history and examination at first visit were superior to 95% in 19,601 records created between January 1976 and December 1987. Patient database interrogation can be used to evaluate the sensitivity and specificity of various signs and symptoms for the diagnosis of secondary hypertension, and to predict, for each patient, his/her cardiovascular risk, the risk of drop-out, the risk of insufficient blood pressure control and the probable blood pressure level. It also serves to test the content and validity of the associated expert system which is progressively built up. A prospective evaluation of the performance of the expert system on 80 cases of hypertension showed overall agreement between the specialists and the expert system ranging from 58 to 91% depending on the decision.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Sleep and hypertension. An epidemiologic study in 7,901 workers].

In order to evaluate possible correlations between blood pressure levels and sleep quality, 7,901 workers of both sexes living in Paris area have been the subject of a survey during their annual examination performed by workside physicians. The enquiry included questions related to sleep quantity and quality, sleeping pills consumption, awakenings, nightmares, snoring, way of life and working conditions. The information concerning these parameters was available for 7,542 people. Among them, 6,551 (86.9%) did not suffer from high blood pressure (HBP) (blood pressure less than 160/95 mmHg), 618 (8.2%) presented a high blood pressure but were not treated, 371 (4.9%) received a treatment against HBP. The average sleep duration is about 7.4 h (S.D. = 1.0) for men and about 7.6 h (S.D. = 1.0) for women (less than 0.001). It is significatively and negatively correlated with the systolic blood pressure level (SBP) (less than 0.001) and the diastolic blood pressure level (DBP) (less than 0.001). The frequency of patients complaining of nightly awakening and of snoring significatively increase with SBP (p less than 0.05) and DBP (p less than 0.001). The observed association between DBP (but not SBP) and sleep duration and nightly awakening remains significant in multivariate analysis including age, sex, tobacco smoking, alcohol and coffee consumption, use of sleeping pills and hypotensive treatment, as well as the negative correlation between SBP and nightmare frequency. The correlation between SBP or SBP and snoring was no more significant. In conclusion, a significant correlation has been found between the blood pressure levels and the sleep quality whose clinical consequences remain to be explored.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Methods and results of arterial hypertension control in a working population].

The health benefits of hypertension treatment at the community level depend both of the quality of the blood pressure control obtained for each patient treated individually and of the percentage of the hypertensive patients actually aware, treated and controlled for hypertension in the entire population. The data collected in 1987 in a group of 7,901 subjects working in medium-sized companies of the Paris region were analysed, and compared with those obtained in a very comparable population in 1979-80. Among patients aware of their disease, the percentage of treated patients was higher in 1987 than in 1979, 55 p. 100 and 46 p. 100 respectively in men (p less than 0.001); 70 p. 100 in 87, 59 p. 100 in 79 for women (p less than 0.01). Hypertension was treated and controlled in 27 p. 100 of the men (16 p. 100 in 1979), and 42 p. 100 of women (27 p. 100 in 1979). Awareness was significantly lower among migrant workers than among european personnel (p less than 0.001). The lower the educational level, the lower the compliance with antihypertensive treatment, ranging from 99 p. 100 for the highest educational level, to 82 p. 100 among low educated subjects (p less than 0.001). The hospitalization rate did not differ according to sociocultural factors. Hypertension was detected by the worksite physician in 51 p. 100 of the male hypertensive patients. He was the sole physician who examined 17 p. 100 of the patients in the previous year. These results suggest a moderate improvement in hypertension detection and control. However, development of intervention strategies and their evaluation are clearly needed.

Adult↗

[Prognostic factors of hypereosinophilic syndrome. Study of 40 cases].

Forty patients with hypereosinophilic syndrome (HES), defined according to the criteria established by Chusid et al., were studied retrospectively in order to determine the prognostic factors in this heterogeneous disease. A myeloproliferative syndrome (MPS) was diagnosed 17 times when splenomegaly and/or a greater than 5 times the normal vitamin B12, level existed. Cutaneous-visceral involvement was almost always present (95%), but could appear after several years of evolution. Twenty-three patients had cardiac involvement, determined by clinical, radiological, electrocardiographic and echocardiographic examinations; 12 of these had endomyocardiac fibrosis. The overall survival rate was 80% at 5 years and 42% at 10 and 15 years. Among the factors evaluated that are capable of influencing this survival, 5 were found to impair the prognosis; presence of an MPS; non-response of the hypereosinophilia to corticoids; existence of a cardiopathy; being male; and an elevated maximum eosinophilia; the last two factors were significantly associated with the cardiopathy. Because hematological or cardiac anomalies are not always present at the time of the first examination, HES patients require very close surveillance.

Actuarial Analysis↗